1. Field of the Invention
The invention concerns an arrangement for the fixing, to a body structure element of a motor vehicle, of a hydraulic control cylinder.
2. Description of the Related Art
The invention concerns more precisely an arrangement for the fixing, to a body structure element of a motor vehicle, of a hydraulic control cylinder with a tubular axial shape overall, notably for controlling a clutch or brakes on the vehicle, of the type in which the control cylinder is movable between a position of mounting in the body structure element of the vehicle, and a position of locking with respect to the body structure element of the vehicle in which it is immobilised with respect to the body structure element of the vehicle by immobilisation means, of the type in which means of immobilising it with respect to translation along the axis of the cylinder include, from front to rear, an abutment surface which extends transversely from a main body of the cylinder, axial elastic means, a wall fixed to the body structure element which has in it an orifice, and at least one bracket, which extends transversely from the main body, which, on mounting, passes through a complementary cutout extending radially from the orifice, the bracket allowing the translational immobilisation of the body with respect to the vehicle body when a rotation of the body about its axis brings it from its mounting position to its locking position and effects the gripping of the wall between the abutment surface, the elastic means and the bracket.
Many examples of arrangements for fixing a hydraulic control cylinder with a tubular axial shape overall to a body structure element of a motor vehicle are known.
First of all conventional arrangements are known, in which the control cylinder is fixed directly to a bulkhead on the vehicle, for example by studs, screws or nuts.
The arrangements of this type have the advantage of using control cylinders which are simple in shape, and therefore inexpensive to produce by casting.
However, these mountings are constraining, the mounting of a control cylinder of the abovementioned type requiring good coaxiality of the anchoring points on the control cylinder and the holes in the bulkhead.
To resolve this drawback, mountings of the type previously described have been conceived, often referred to as "bayonet" mountings, which allow a rapid mounting or demounting of the control cylinder in the body structure element in the vehicle, notably the vehicle bulkhead.
The document GB-B-2.163.475 describes an arrangement of this type in which the control cylinder has three brackets which simultaneously effect the translational immobilisation and the rotational immobilisation of the control cylinder.
To this end, the control cylinder has a U-shaped elastic pin which is slipped radially onto two parallel countersinks on the cylinder body, which is in abutment on a front face of the support and in abutment on a rear face of a radial collar on the body of the control cylinder. The control cylinder also has three brackets uniformly distributed angularly, whose front faces have teeth which are intended to cooperate with notches on a rear face of the support, when the elastic pin axially acts on the body of the control cylinder.
This arrangement has the drawback of requiring a suitable angular positioning of the teeth on the cylinder opposite the notches in the support, which makes mounting tricky.
In addition, the particular shape of the brackets requires a mould with a particularly complex shape and an expensive casting process, the surface state of the teeth being necessary to a good positioning of the control cylinder with respect to the vehicle bulkhead.